Not sure how to start making patterns? Do you struggle with the maths of calculating accurate middle (gusset) pieces. This is the tool for you!
I have previously released a Inkscape extension that can automatically generate patterns from shapes drawn, such as bag side panels. Not everyone has access to or uses Inkscape, so I’m working on bringing that key functionality to an online tool. Nearly instant patterns for backpacks, bike bags (frame bags, top tube bags etc) and more.
Work in progress! Might have some bugs. Test with a paper model or scrap fabric before committing to your expensive materials.
Want to support development of more free tools?
These free tools take up a significant amount of my limited personal time so any support is appreciated 🙂
Please donate via Paypal or Ko-fi or purchase a random pattern from this website
Start Drawing!
Background Image (e.g. Bicycle Frame)
or use a line segment to scale from
Instructions:
Draw your shape by clicking or tapping on the canvas.
Add gusset split points. Where you want a split/new pattern piece in the gusset (perimeter side loop), tap an existing point. Split points are shown with red markers.
Delete points by clicking any red split point.
Move points by clicking/tapping and dragging any point
Add new points on lines by tapping/clicking anywhere along a line segment
Add seam allowance by pressing enter or click the Finish Shape/Add Seam allowance button to complete the shape. A helpful 3D view also appears! You can adjust the seam allowance in the pattern generation options
Scaling is adjusted by either specifying the actual real world dimensions of each grid square, or choosing a line segment and specifying the known length of that segment
Background image for tracing is added by clicking the browse button, and opacity can be adjusted. If the background image has wonky perspective, please use my free perspective correction tool before tracing. No images are uploaded to me, this all runs locally on your device.
Pattern Generation: Specify how wide you want the bag to be (use the 3D view to visualise) and the seam allowance, then click Generate Pattern (or type P).
You will now have a automatically generated pattern, ready to cut out and sew!
Printing and Assembling:
Patterns must be printed at 100% or “Actual Size” or equivalent in your printer settings. Use the scale box to check your printout before cutting fabric.
Cut along the borders and tape the borders together.
Made something cool? I’d love to see. Feel free to share your creations via the social links at the top of the page, reddit.com/r/myog or the contact form.
Known Quirks:
- You can draw whatever, but doesn’t mean you can sew it. For example, patterns with sharp inwards corners you will struggle to sew. Again, test on scraps before fully committing.
- Might have bugs. Test whatever you generate with a paper model or scrap fabric before committing to fabric.
- Linear segments only currently. I might look into curved corners and beziers in the future. For now, just draw lots of points to simulate curves, and move the points if you need to adjust them. Your sewing accuracy will be less than the points not being a perfect curve.
- Wide gussets (wider than the paper width) aren’t tiled.
Sewing Instructions
For general instructions related to frame bags, which are a perfect example of what this tool can be used for, see this article:
Changelog:
14 Feb 2025: Any attached background image can now be optionally included in exported PDF
30 Jan 2025: Volume shown in 3D view area. Slight UI styling adjustments
23 Jan 2025: Workflow Change!
- All point editing functionality is now possible before adding the seam allowance. Functions the same on mobile and desktop, with clicking a point to add, then again to make a split point, then again to delete. No right click needed anymore.
- Clearer scale box on first page instead of text dimensions
Show older changelog
28 Nov 2024: User interface improvements, instructions added.
17 Nov 2024:
- Gusset piece dimensions listed in the PDF so you don’t have to print the pages
- One single PDF generated for the entire project
9 Nov 2024: Fixed bug when generating patterns with gussets larger than page width that caused freezing
6 Nov 2024: 3D view to help visualise your project
4 Nov 2024 –
- Page orientation now auto-calculated in the drawn polygon PDF to be paper efficient.
3 Nov 2024 –
- Fixed bug so resizing the canvas now keeps points relative to background image.
2 Nov 2024 –
- Added saving and loading your pattern. NOTE: this generator is a work in progress and your save files might stop working in the future as new features are added
1 Nov 2024 –
- Better seam allowance algorithm and alignment lines.
- Choice of canvas sizes for more accurate drawing around images.
- Should be more mobile friendly now. Best to rotate your screen landscape as you currently cant scroll side to side to see more of the canvas
24 Oct 2024 –
- Add background image
- Scale any segment to known length. Much easier than manually tweaking grid size to get the dimensions you require for the background image.
- Cutting border and overlap in generated PDFs instead of aligning page edges
22 Oct 2024 – Multiple gussets on a sheet to save paper
21 Oct 2024 – Last point of gusset is now also labelled.
Added A0 and A3 paper sizes
12 Oct 2024 – Quickstart message, ability to add extra points and remove them
12 Oct 2024 – Labelling of angles and every segment length
10 Oct 2024 – First release
